SIOUX FALLS, S.D. (AP) — A storm carrying at least one tornado struck South Dakota's largest city overnight, leaving a trail of destroyed buildings, downing power lines and prompting the rapid but safe movement of dozens of patients in a hospital that was damaged by powerful winds, officials said Wednesday.
National Weather Service meteorologist Todd Heitkamp said an EF-2 tornado that touched down in Sioux Falls with wind speeds of about 125 mph around 11:30 p.m. Tuesday caused significant damage in and around the Western Mall.
Elsewhere in the city, Avera Health System hospital staff took mere minutes to move more than 100 patients to safety in one of four buildings that suffered damage.
"We talk at our hospital about doing drills. I've got to tell you our staff was courageous," said David Flicek, the president and CEO of Avera McKennan Hospital and University Health Center. "We had 10 minutes to wake up 102 residents, get them to the center of the building and all are safe and sound."
Seven people suffered minor injuries from falling debris, Flicek said.
Nick Gibbs, CEO of Avera Heart Hospital, said one patient had a "severe cardiac event" as the storm threatened that facility, but doctors saved his life.
The storm ripped off part of the roof and caused significant damage to windows at the behavioral health building, according to Avera spokeswoman Michelle Pellman. Many vehicles in the parking lots were destroyed.
The National Weather Service is examining the hospital campus to determine if it was also struck by a tornado or if the damage was inflicted by powerful straight-line winds.
Mayor Paul TenHaken said officials have received no reports of deaths in the city, and that they had been "fortunate to not have any serious injuries."
At least 37 buildings collapsed or were damaged by the storm, and residents have been asked to stay away from the hardest-hit areas, Fire Chief Brad Goodread said at a news conference early Wednesday.
Other damaged businesses included an Advanced Auto Parts store where a wall collapsed. Kohl's and Best Buy lost part of their roofs and Pizza Ranch suffered heavy damage.
The Red Cross opened a shelter at the Sioux Empire Fairgrounds' armory for people displaced by the storm. The city of about 190,000 people lies about 240 miles (390 kilometers) southwest of Minneapolis.
Heitkamp said the weather service issued several warnings as the fast-moving storm approached, including a tornado warning at 11:27 p.m.
At 11:30 p.m., members of the weather service office in Sioux Falls took shelter and transferred duties to a sister office in northeastern South Dakota, he said.
There was a snafu with the city's outdoor siren warning system. Most of the sirens sounded in southeastern Sioux Falls, where the most serious damage occurred, but they were not activated in the rest of the city, TenHaken said, calling it a "miscommunication" among staff. He vowed it would never happen again.
"I'm owning it. It's my team. It's my administration," the mayor said.
Xcel Energy says as many as 25,000 customers were without power at one point because of the damage, but that more than two-thirds of those had electricity Wednesday morning.
The storm system appears to have spared the rest of the state. The South Dakota Department of Public Safety received reports of flooding in Hutchinson and Brule counties, but no assistance was requested.
The weather service warned of possible severe thunderstorms Wednesday across the Plains and Upper Midwest, stretching from western Nebraska, Minnesota and Iowa to Wisconsin. The likeliest threat was in western Nebraska, and the weather service warned of possible flash flooding in the north-central part of the state.